Method of treating rheumatoid arthritis

ABSTRACT

A method is described for relieving and inhibiting the symptoms of inflammatory rheumatoid arthritis in mammals using cetyl myristoleate.

This application is a continuation-in-part of my copending applicationSer. No. 682,540, filed May 3, 1976, now U.S. Pat. No. 4,049,824 issuedSept. 20, 1977.

The present invention relates to a method for relieving and inhibitingat least one of the symptoms of inflammatory rheumatoid arthritis inmammals by administering orally, topically or parenterally atherapeutically effective amount of cetyl myristoleate

    CH.sub.3 (CH.sub.2).sub.15 OCO(CH.sub.2).sub.7 CH═CH(CH.sub.2).sub.3 CH.sub.3

which may be extracted from the tissues of mice or producedsynthetically. Osteoarthritis is one of the oldest and most commoninflammatory diseases in mammals. It occurs at all ages. Studies showthat 97% of all persons over age 60 have an arthritic condition whichcan be observed by X-ray. The most common symptoms of arthritis arepain, fever and inflammation, and it is the No. 1 crippling disease inman.

An object of the present invention is to provide a method for relievingand inhibiting the symptoms of inflammatory rheumatoid arthritis inmammals.

Another object of the invention is to inhibit the symptoms, such aspain, fever and inflammation associated with inflammatory rheumatoidarthritis in mammals by administering orally, topically or parenterallycetyl myristoleate extracted from the tissues of mice.

These and other objects will became apparent in the following detaileddescription of the invention.

It is well known that Freund's adjuvant will induce poly-arthritis inrats but not in mice. It has been common practice to test variouscompounds and compositions in laboratories to determine theireffectiveness in relieving the symptoms of inflammatory rheumatoidarthritis by administering test compounds or compositions to rats havingpoly-arthritis induced previously by administering Freund's adjuvant. Itwas hypothesized that mice must contain some protective factor ormechanism which prevented the inducement of poly-arthritis in mice.

In accordance with the present invention a substance has been isolatedfrom mice which, when administered to rats, essentially prevents theformation of poly-arthritis and the resultant symptoms when the rats aresubsequently injected with Freund's adjuvant. The substance was isolatedby extracting homogenized whole mice with methylene chloride. Uponpurification of this extracted substance it was identified as cetylmyristoleate. The following example describes in greater detail theisolation of the effective substance from mice.

EXAMPLE I

Seventy-nine mice totalling 2300 grams were macerated in an electricblender in batches of about eight mice, each batch being macerated in400 ml methylene chloride. The final blend was poured into a 4 literbeaker. The blend was stirred until the methylene chloride separated,then the mixture was filtered under light suction through a largeBuchner funnel containing filter paper covered by a thin layer ofFilter-Cel. The resultant precipitate was washed with two 100 mlportions of methylene chloride. The combined filtrate and washings wereseparated from a top layer of water after which the methylene chloridewas filtered again. This filtrate was concentrated in vacuo to a thinsyrup of 167 grams which was treated with four parts of acetone and thenleft at -5° C. for three days with brief stirring each day.

The mixture was filtered using Buchner filter paper with a layer ofFilter-Cel and light suction. The precipitate was washed with four 25 mlportions of -5° C. acetone. The combined filtrate and washings wereconcentrated in vacuo to a thin syrup of 121 grams. This material wasdissolved in 500 ml of 20:1 legroin (20°-40° C.), dry ether andchromatographed on 2500 ml 40-325 mesh ASTM silica gel in an appropriatecolumn using the 20:1 legroin-ether mixture as eluent. One 1500 ml"blank" and then eleven 100 ml and six 200 ml fractions were collected.

Fraction Nos. 3-15 inclusive were combined and filtered in vacuo through120 grams of Darco-X. The filtrate was concentrated in vacuo to a syrupof 0.15 gram. The Darco-X was further washed with several portions ofmethylene chloride. The 0.15 gram of syrup was dissolved in thesewashings which were concentrated in vacuo to a syrup of 0.8 gram ofcrude material. This was chromatographed using 350 ml of silica gel,70-325 mesh ASTM using 40:1 carbon tetrachloride-ether as eluent.

Fraction Nos. 67-79 of 7 ml each gave 0.4 gram of material which wasrechromatographed with 125 ml of silica gel using 60:1 carbontetrachloride-ether in 2.5 ml fractions.

Fraction Nos. 117-127 gave 0.15 gram of purified syrup which proved tobe principally the desired cetyl myristoleate (v_(max) ^(neat) 1782cm⁻¹). Extensive thin-layer chromatography and frequent bioassays wereused throughout to monitor the isolation and purification of thecompound.

The following example describes the steps taken to identify the cetylmyristoleate product of Example I.

EXAMPLE II

A mixture of 0.15 gram of the material obtained in Example I was heatedwith 2 ml of acetone and 3 ml of 10% sodium hydroxide solution underreflux with stirring for fourteen hours and then treated with 0.7 ml of12 M HCl. Extractions were made with four 5 ml portions of methylenechloride followed by drying with Na₂ SO₄ and then evaporated withmethylene chloride in vacuo. The 0.14 gram of material recovered waschromatographed on 140 ml of silica gel with methylene chloride aseluent. A 400 ml and one hundred ten 6 ml fractions were collected.

Fraction Nos. 20-55 gave 40 mg of cetyl alchohlol having a melting pointof 49°-50° C. after recrystallization from ethanol. The analysiscalculated for C₁₆ H₃₄ O is

C -- 79.3%

h -- 14.1%

the analysis found was

C -- 79.2%

h -- 14.3%

fraction Nos. 89-110 produced 60 mg of a syrup which was furtherpurified by chromotography. The resultant acid gave (v_(max) ^(neat)1712, 1722 (sh cm⁻¹). The analysis calculated for C₁₄ H₂₆ O₂ is

C -- 74.4%

h -- 11.6%

neut. equiv. -- 226.3

What was found is as follows:

C -- 74.1%

h -- 11.9%

neut. equiv. -- 225.5

EXAMPLE III

A charge of 150 mg of cetyl alcohol, 150 mg of myristoleic acid, 50 mgof p-toluenesulfonic acid monohydrate of 20 ml of benzene were heatedtogether under reflux conditions for four hours and then washed with a10% sodium hydroxide solution. The benzene layer was recovered, driedand evaporated in vacuo.

This procedure produced 300 mg of a mobile oil which was identified ascetyl myristoleate (v_(max) ^(neat) 1782 cm⁻¹)(nuclear-magnetic-resonance and infrared spectoscopy).

EXAMPLE IV

Following the procedure set out in Example II, 150 mg of cetyl alcoholobtained in Example III and 150 mg of the acid obtained in Example IIproduced 300 mg of an ester (v_(max) ^(neat) 1782 cm⁻¹) which wasidentified by similar means with the products in Examples I and III.

Both the cetyl myristoleate extracted from the tissues of mice asdescribed in Example I and cetyl myristoleate prepared synthetically asdescribed in Example III have been found to be effective in relievingand inhibiting the symptoms of rheumatoid arthritis.

When administered orally the cetyl myristoleate may be administered inthe pure state or preferably with known pharmaceutically acceptablevehicles or solvents such as Tracanth-Acacia, an emulphor-system such asis described in J. Pharm. Pharmacol., 25:344-345 (1973), propyleneglycol or a vegetable oil such as corn or peanut oil. The relativeproportions of vehicle and cetyl myristoleate are not critical. Thedaily dosage of cetyl myristoleate preferably ranges between about 0.05and 0.75 gm for each 140-200 gms weight of the animal.

When administered topically the cetyl myristoleate is preferablyadministered with a vehicle capable of being absorbed through thesurface of the skin. A preferred vehicle is dimethyl sulfoxide (DMSO).The relative proportions of vehicle and cetyl myristoleate again are notcritical. The daily dosage of cetyl myristoleate administered topicallypreferably ranges between about 0.05 and 0.75 gm. for each 140-200 gmsweight of the animal.

When administered parenterally a vehicle such as mineral oil ispreferably used. Again the relative proportions of vehicle and cetylmyristoleate are not critical and the daily dosage of cetyl myristoleateis preferably between about 0.05 and 0.75 gm for each 140-200 gms weightof the animal.

EXAMPLE V

The cetyl myristoleate produced both synthetically and by isolation fromwhole mice, respectively, were administered parenterally in mineral oilas a compatible carrier to male rats (Sprague Dawley Strain) ranging inweight between 140 and 200 grams. It is not necessary, however, that acarrier be used since cetyl myristoleate is itself an oil.

One set of rates was innoculated subcutaneously with 1.0 ml each of amixture of mineral oil and 0.05 gm of the cetyl myristoleate.Twenty-four hours later the rats were innoculated with Bacto m.Butyricum (Disco 0640-33). A control group received only the Butyricum.

Another set of rats were given 1.0 ml each of a mixture of mineral oilcontaining 0.075 gm of the synthetically produced cetyl myristoleate.Two days later the rats were innoculated with Bacto m. Butyricum (Disco0640-33). Another control group received only the Butyricum.

The rats in both control groups developed severe poly-arthritis duringthe following 10- to 18-day period which persisted through 32 days. Allof these rats gradually lost weight.

About 70% of the first group (those treated with the material extractedfrom mice plus Butyricum) were completely protected from thepoly-arthritis. They showed no swelling or other symptoms. The other 30%were partially protected during the 32-day period.

All of the second group (those treated with synthetically produced cetylmyristoleate plus Butyricum) were protected from the poly-arthritis andshowed a steady gain in weight.

It was found that the purer the cetyl myristoleate the more dramaticwere the results in protecting the rats from poly-arthritis. Also, aneffective dosage of cetyl myristoleate preferably ranges between 0.05and 0.75 gm for each 140-200 gms weight of the animal. However, dosessmaller than and greater than this range will effectively relieve andinhibit the symptoms of rheumatoid arthritis such as pain, fever andinflammation.

Thus having described the invention in detail, it will be understood bythose skilled in the art that certain modifications and variations maybe made without departing from the spirit and scope of the invention asdescribed herein and defined in the appended claims.

I claim:
 1. A method of relieving and inhibiting the symptoms ofinflammatory rheumatoid arthritis in mammals which comprises the oraladministration to a mammal of an effective amount of cetyl myristoleate.2. A method according to claim 1 wherein said cetyl myristoleate isadministered with a compatible pharmaceutical carrier.
 3. A methodaccording to claim 2 wherein said compatible pharmaceutical carrier isselected from the group consisting of Tracanth-Acacia, propylene glycol,corn oil and peanut oil.
 4. A method according to claim 1 wherein about0.05-0.75 gm of cetyl myristoleate is administered for each 140-200 gmsweight of the mammal.
 5. A method of relieving and inhibiting thesymptoms of inflammatory rheumatoid arthritis in mammals which comprisesthe topical administration to a mammal of an effective amount of cetylmyristoleate.
 6. A method according to claim 5 wherein said cetylmyristoleate is administered with a compatible pharmaceutical carrier.7. A method according to claim 6 wherein said compatible pharmaceuticalcarrier is dimethyl sulfoxide.
 8. A method according to claim 5 whereinabout 0.05-0.75 gm of cetyl myristoleate is adminstered for each 140-200gms weight of the mammal.